sodick A535 error codes

[LaserToolShop]

It's not the first time. Just after system has loaded, those messages appears on my sodick A535 MK25.
E064 error 64 has occured (SH) press ACK
or
E065 error message 65 has occured (63) press ACK
and when hit ACK key
E171 alarm in nc power.
just one time
E201 power down (63) press ACK.
Usually, I plug out and replug in ST and EFII pcboards connectors on cabinets and machine restart but I never knew exactely what's wrong ?
I try to learn how to use IN-OUT tables on SET-CHCK menu, but I don't understand what I have to check or change on those tables.
Could you have an idea ?
Thanks a lot

[LaserToolShop]

E064 error 64 has occured
(SH) press ack persist !
I tried to reboot directely PC's machine.
System loading progress from 11 to 48 and show yellow message Sys2/Sys3.
Would it be hasardous reloading floppy disk systems 2 and 3 ?
I suspect ST pcb's function to blame.
Did someone have similar experience?
In the past i had several times E078 error78 (SH), I found to restart by plug out replug in pcb, but I never known why.